How to beginner · 3 min read

How to choose between Claude models

Q: How to choose between Claude models

Choose between Claude models by evaluating your needs for response quality, speed, and cost. Use claude-3-5-sonnet-20241022 for the highest coding and reasoning performance, claude-3-5-haiku-20241022 for faster, lighter tasks, and claude-3-opus-20240229 for balanced general-purpose use.

Quick answer

Choose between Claude models by evaluating your needs for response quality, speed, and cost. Use claude-3-5-sonnet-20241022 for the highest coding and reasoning performance, claude-3-5-haiku-20241022 for faster, lighter tasks, and claude-3-opus-20240229 for balanced general-purpose use.

PREREQUISITES

Python 3.8+
Anthropic API key
pip install anthropic>=0.20

Setup

Install the Anthropic Python SDK and set your API key as an environment variable to authenticate requests.

bash

pip install anthropic>=0.20

Step by step

Use the Anthropic SDK to call different Claude models. Below is a runnable example demonstrating how to send a prompt to claude-3-5-sonnet-20241022 and print the response.

python

import os
import anthropic

client = anthropic.Anthropic(api_key=os.environ["ANTHROPIC_API_KEY"])

response = client.messages.create(
    model="claude-3-5-sonnet-20241022",
    max_tokens=200,
    system="You are a helpful assistant.",
    messages=[{"role": "user", "content": "Explain the difference between Claude models."}]
)

print(response.content[0].text)

output

Claude-3-5-sonnet-20241022 is optimized for complex reasoning and coding tasks, offering the highest accuracy and detail. Claude-3-5-haiku-20241022 is faster and lighter, suitable for simpler or latency-sensitive applications. Claude-3-opus-20240229 balances speed and capability for general use.

Common variations

You can switch models by changing the model parameter in the client.messages.create call. For example, use claude-3-5-haiku-20241022 for faster responses or claude-3-opus-20240229 for balanced tasks. Async calls and streaming are also supported by the SDK.

python

import asyncio
import os
import anthropic

async def async_call():
    client = anthropic.Anthropic(api_key=os.environ["ANTHROPIC_API_KEY"])
    response = await client.messages.acreate(
        model="claude-3-5-haiku-20241022",
        max_tokens=150,
        system="You are a helpful assistant.",
        messages=[{"role": "user", "content": "Summarize the benefits of Claude models."}]
    )
    print(response.content[0].text)

asyncio.run(async_call())

output

Claude models offer a range of options balancing speed, cost, and capability, allowing you to pick the best fit for your application needs.

Troubleshooting

If you encounter authentication errors, verify your ANTHROPIC_API_KEY environment variable is set correctly. For rate limit errors, consider reducing request frequency or upgrading your plan. If responses are incomplete, increase max_tokens.

✅

Key Takeaways

Use claude-3-5-sonnet-20241022 for highest accuracy and complex tasks.
Choose claude-3-5-haiku-20241022 for faster, lightweight responses.
Select claude-3-opus-20240229 for balanced general-purpose use.
Switch models easily by changing the model parameter in the SDK call.
Always set your API key in os.environ to avoid authentication issues.

Verified 2026-04 · claude-3-5-sonnet-20241022, claude-3-5-haiku-20241022, claude-3-opus-20240229

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